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Braya longii (Long’s braya), Braya fernaldii (Fernald’s braya), and Disturbance on Newfoundland’s Great Northern Peninsula by Hilary Janes A thesis in partial fulfillment of the requirements for the degree of Bachelor of Science (Geography) Department of Geography Memorial University of Newfoundland January 1999 St. John’s Newfoundland and Labrador Acknowledgements The author would like to thank her advisor, Karyn Butler, for her invaluable guidance during the writing of this thesis. Thanks also to Luise Hermanutz for involving the author in the Braya Recovery Project and for providing the materials needed to complete this thesis. Finally, the author would like to thank Stephen Rowe for his assistance with the mapping and GIS portions of this project. i Table of Contents Page # List of Figures iv List of Tables v Abstract vi Chapter 1: Introduction 1 1.1 Background Information 1 1.2 Study Objectives 3 1.3 Overview of Methods 4 Chapter 2: Literature Review 5 2.1 Organization of literature Review 5 2.2 Limestone 5 2.3 Disturbance 7 2.4 Braya 11 Chapter 3: Study Area 17 3.1 Yankee Point 19 3.2 Savage Point 19 3.3 Sandy Cove 20 3.4 Watt’s Point 20 3.5 Cape Norman 20 3.6 Burnt Cape 21 Chapter 4: Methods 22 ii Page # Chapter 5: Results 26 5.1 Yankee Point 33 5.2 Savage Point 34 5.3 Sandy Cove 35 5.4 Watt’s Point 36 5.5 Cape Norman 37 5.6 Burnt Cape 38 Chapter 6: Discussion and Conclusions 39 6.1 Density 39 6.2 Disturbance 42 6.3 Conclusions 33 References 44 iii List of Figures Page # Figure 1: map of Newfoundland showing the limestone barrens 2 ecoregion Figure 2: a portion of the limestone barrens at Watt’s Point 6 Figure 3: a specimen of Braya fernaldii in fruit at Burnt Cape 12 Figure 4: map of study area showing Fernald’s original Braya 13 populations that still exist, those that have disappeared and potential sites searched by Braya Recovery Team Figure 5: quarrying at Sandy Cove 15 Figure 6: map of study area showing Braya locations 18 Figure 7: measuring population density at Burnt Cape using a 25 1 m square quadrat Figure 8: temporal change in total area of disturbance at each study 28 site (1948 - 1995) Figure 9: location of Braya population and area of disturbance at 29 Yankee Point Figure 10: locations of Braya populations and area of disturbance at 29 Savage Point and Sandy Cove Figure 11: location of Braya population and area of disturbance at 30 Watt’s Point Figure 12: location of Braya population and area of disturbance at 30 Cape Norman Figure 13: location of Braya population and area of disturbance at 31 Burnt Cape iv List of Tables Page # Table 1: description of aerial photos of study sites (1948-!995) 23 Table 2: area of disturbance at each Braya site (m²) 27 Table 3: habitat disturbance level and density measurements (per m²) 32 of Braya populations for each study site v Abstract: Braya longii (Long’s braya) and Braya fernaldii (Fernald’s braya) are small arctic-alpine plants which grow only on the limestone barrens of northern Newfoundland. They thrive in areas which are subjected to small-scale disturbance, such as frost heaving, because it prevents other plants from establishing in preferred Braya habitat. Braya longii and B. fernaldii also grow well in areas that have been disturbed slightly by anthropogenic activity. Unfortunately, extensive limestone quarrying on Newfoundland’s Great Northern Peninsula has destroyed a significant amount of Braya habitat and, as a result, a very limited number of small populations still exist. In 1997, COSEWIC designated Braya longii as endangered and Braya fernaldii as threatened. In this study the temporal change in anthropogenic disturbance at each study site is investigated through the use of a Geographic Information System. The results generated by this method indicate that the amount of man-made disturbance on the Northern Peninsula has increased dramatically over the last 50 years. This information is necessary to emphasize the need to protect Braya populations from further large-scale anthropogenic disturbance. This study also uses population density measurements to examine the effect of different levels of disturbance (anthropogenic and natural) on the vitality of Braya populations. Such information may provide an understanding of the preferred habitat of Braya which may aid in the future management of these populations. vi Chapter 1: Introduction 1.1 Background Information During the summers of 1924 and 1925, Harvard botanist, M.L. Fernald, and his companion, Bayard Long, undertook an extensive survey of the flora of Newfoundland. On the Great Northern Peninsula, in particular, they documented a variety of spectacular plant species. Some of Fernald’s and Long’s interesting discoveries included two species of Braya, an arctic genus which had not previously been found so far south. At the time of their discovery Fernald considered these two species, known as Braya longii (Long’s braya) and Braya fernaldii (Fernald’s braya), “common” along the Strait of Belle Isle (Fernald, 1926). Braya longii and B. fernaldii grow only on the limestone barrens found along the Strait of Belle Isle and on the northern portion of Newfoundland’s Great Northern Peninsula (Figure 1). They typically occupy areas of limestone gravel that have been disturbed by frost heaving and may also be found in areas of small-scale anthropogenic disturbance. Such disturbances are critical to the survival of these species since they eliminate competition from preferred Braya habitat. However, Braya longii and B. fernaldii cannot tolerate large-scale anthropogenic disturbance, such as quarrying, as it destroys potential Braya habitat and removes populations. Extensive limestone quarrying on the Great Northern Peninsula has already destroyed many Braya populations and the few remaining populations are at risk of being eliminated. If quarrying is allowed to continue at the sites occupied by Braya populations there is a good possibility that these two species will become extinct. Braya longii and B. fernaldii are not protected by legislation in Canada or Newfoundland even though they were designated as endangered and threatened, respectively, by COSEWIC (Committee on the Status of Endangered Wildlife in Canada) in 1997. Recently, a Braya Recovery Team was 1 Strait of Belle Isle Limestone Barrens N E W F O U N D L A N D Figur e 1: map of Newfoundland showing the location of the limestone barrens (Meades, 1990). 2 formed to monitor the remaining Braya populations and to help find a way to preserve them. This team is seeking habitat protection in the form of reserves, stewardship initiatives, and education programs and is currently undertaking an immediate (provincial) preservation for the seriously “at risk” populations (Hermanutz, 1998). In 1997, Burnt Cape, one of the Braya fernaldii sites, was designated as a “Provisional Reserve” by the Newfoundland government and should attain full Reserve status in the near future. Such status will protect this area and the plants inhabiting it from future quarrying. 1.2 Study Objectives The main objective of this study is to classify disturbance at each of the Braya sites as either natural, high anthropogenic, or low anthropogenic based on aerial photo analysis. The amount of each type of disturbance that was created at each site between 1948 and 1995 will then be quantified. Analyses of the different levels of disturbance and of the increase in disturbance on Newfoundland’s limestone barrens over the last 50 years should provide an indication of the long-term stability and viability of this type of habitat. Hopefully, this information will aid the Braya Recovery Team in obtaining protection for Braya longii and B. fernaldii. Another objective of this study is to provide information about the effects of different levels of disturbance (natural and anthropogenic) on the vitality of Braya populations through the comparison of population densities. Such information will help provide a better understanding of the dependence of Braya on different types of disturbance and of the historical population dynamics of these Braya species. 3 1.3 Overview of Methods In order to quantify the amount of disturbed habitat at each of the Braya sites areas of disturbance, such as gravel pits, were identified on aerial photos that were taken in 1948, 1968, 1979, and 1995. Classification of these disturbed areas as either natural, high anthropogenic, or low anthropogenic was attempted by analysing the aerial photos with a stereoscope. Ground-truthing at each of the study sites was later conducted to determine whether or not disturbed areas had been classified correctly. The aerial photos were then traced onto mylar sheets and the disturbed areas were outlined. Once the outlines had been imported into a Geographic Information System the areas of disturbance were digitized and then queried to determine the total area of disturbance at each site for each of the four years. The vitality of Braya populations growing in naturally and anthropogenically disturbed areas was determined by taking density measurements. At each study site, the type of disturbance was noted and a one meter square quadrat was randomly tossed throughout the Braya population five times. After each toss the number of plants within the quadrat was counted. The results of the density measurements were then compared to determine whether populations had the greatest densities in areas of natural, high anthropogenic, or low anthropogenic disturbance. 4 Chapter 2: Literature Review 2.1 Organization of the Literature Review The literature review is divided into three components: limestone, disturbance, and Braya. Since Braya longii and B. fernaldii grow in limestone a section describing this type of rock and the characteristics of the limestone barrens, where these species are found, is essential.

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